21665895226 has 8 divisors (see below), whose sum is σ = 33547192704. Its totient is φ = 10483497660.

The previous prime is 21665895169. The next prime is 21665895227. The reversal of 21665895226 is 62259856612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21665895226² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21665895227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 174724900 + ... + 174725023.

It is an arithmetic number, because the mean of its divisors is an integer number (4193399088).

Almost surely, 2^21665895226 is an apocalyptic number.

21665895226 is a deficient number, since it is larger than the sum of its proper divisors (11881297478).

21665895226 is a wasteful number, since it uses less digits than its factorization.

21665895226 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349449956.

The product of its digits is 3110400, while the sum is 52.

The spelling of 21665895226 in words is "twenty-one billion, six hundred sixty-five million, eight hundred ninety-five thousand, two hundred twenty-six".